Kostas Manolas (right) tussles for the ball with Costa Rica and Arsenal forward Joel Campbell during the World Cup.Getty Images

Arsenal are reportedly interested in making a surprise swoop for Kostas Manolas from Olympiakos in the ongoing transfer window.

The Metro's report states that the Gunners have earmarked the 23-year-old as a direct replacement for Thomas Vermaelen. The Belgian international is believed to be on the verge of leaving the Emirates with Manchester United waiting in the wings for his signature.

Earlier reports suggested that the Red Devils are hoping to complete the transfer as soon as Marc Wilmots' side are knocked out of the World Cup. United were hoping to secure the defender's services for just £6m but are now bowing down to meet the north London club's demands of £10m.

Belgium were knocked out on Saturday by Argentina and Vermaelen's move to Old Trafford could pick up pace. Arsenal manager Arsene Wenger will be with only two regular centre-backs in Per Mertesacker and Laurent Koscielny and wants to bolster his back four with some quality additions.

The 64-year-old Frenchman has set his sights on the Greek international owing to his consistent performances for Olympiakos that helped them win the league title. Manolas, who still has two years left on his contract, played all the matches for Fernando Santos' side at the World Cup as Greece bowed out in the pre-quarterfinals.

The report also suggests that Manolas is valued at £8m by his current employers and the FA Cup holders might have to move swiftly for the centre-back's signature as Juventus are also said to be keen on signing him this summer.

Manolas arrived at the Karaiskakis Stadium from AEK Athens on a free transfer and has established himself as one of the best defenders in Greece. He made 25 appearances in the Greek Super League last season scoring three goals.

Meanwhile, Arsenal are also reportedly in the hunt along with their archrivals Tottenham Hotspur to sign Netherlands defender Joel Veltman from Ajax.